The MCD Biology training program will provide intensive training in the skills necessary for outstanding research in modern, molecular, cellular, and developmental biology. The structure of the training program has been established and refined during the past 10 years. Incoming graduate undertake intensive coursework aimed at providing a solid framework upon which to build during their graduate careers, emphasizing critical evaluation of scientific models, experimental approaches, and results. First-year trainees participate in a laboratory rotation program in which they carry out ten-week research projects in three different laboratories, thereby gaining exposure to a number of different experimental systems. Second year students are required to pass an oral qualifying exam, and advanced students participate in a variety of seminars, advanced special topics courses, and research group meetings designs to provide continuing learning opportunities. The goal of the training program is to produce outstanding graduates who have a strong foundation in the specific area of their thesis research, and who are broadly trained in molecular, cellular, and developmental biology. The hallmarks of our program are an outstanding, young, and highly interactive faculty, close faculty-student interaction, and high-quality graduate training. Research in the MCD Biology program is organized in clusters of faculty with shared interests, thereby creating critical masses of researchers to foster mutual support and scientific interaction. One such cluster, encompassed by the Markey Center for the Molecular Biology of RNA, is internationally recognized for the study of RNA. The foci of the other research cluster include developmental biology, cell biology, structural biology, and plant molecular biology. Students in the MCD Biology training program are therefore exposed to a wide range of different experimental problems and systems. We are requesting support for a total of 6 predoctoral student positions during the first year of the program which will be awarded to recruit outstanding students and to encourage excellence in the performance of our best students. Administration of the training program will be under the direction of an Executive Committee and the Program Director.